# nasa-exoplanets — licence and redistribution status

STATUS: this file documents a licence, not a measurement. Nothing in this
benchmark has been measured yet (see the top-level README.md).

## Source

NASA Exoplanet Archive, *Planetary Systems Composite Data* table
(`pscomppars`), queried through the TAP sync service with a pinned query
(columns and `ORDER BY pl_name ASC` make the snapshot deterministic up to the
archive's monthly refresh):

> https://exoplanetarchive.ipac.caltech.edu/TAP/sync?query=SELECT%20TOP%203000%20pl_name,hostname,sy_snum,sy_pnum,discoverymethod,disc_year,pl_orbper,pl_rade,pl_bmasse,pl_eqt,st_teff,st_rad,st_mass,ra,dec%20FROM%20pscomppars%20ORDER%20BY%20pl_name%20ASC&format=csv

The committed `nasa-exoplanets.csv` (sha256 in `../PROVENANCE`) is the
canonical copy the gold-derivation script reads.

## Licence terms we could verify, quoted verbatim

The archive's service pages carry **no explicit open-licence statement**; what
they do carry is an acknowledgment request. From
https://exoplanetarchive.ipac.caltech.edu/docs/acknowledge.html, fetched live
from this sandbox on 2026-09-29 (UTC, sandbox clock):

> "Please include the following standard acknowledgment in any published
> material that makes use of the NASA Exoplanet Archive's services. This
> research has made use of the NASA Exoplanet Archive, which is operated by the
> California Institute of Technology, under contract with the National
> Aeronautics and Space Administration under the Exoplanet Exploration
> Program."

Acknowledgment given here in exactly those words.

## Honest assessment

- No redistribution restriction of any kind was found on the archive pages we
  could reach (acknowledge.html and the service landing pages; fetched
  2026-09-29, sandbox clock).
- The archive is NASA-funded and operated by Caltech under NASA contract;
  works of the U.S. Government are not subject to copyright in the U.S.
  (17 U.S.C. § 105). We therefore treat this as public-domain-by-statute
  government data with the requested acknowledgment — and we say plainly that
  the archive itself does not print the words "public domain" anywhere we
  could fetch.
- If a stricter reading is ever wanted, swapping this dataset for a CC-BY- or
  CC0-marked table is a drop-in change: the derivation script reads columns,
  not URLs.
